Apparatus for sealing metal to glass



June 21, 1938- J. F. DONOVAN El A1,. 2,121,627

APPARATUS FOR SEALING METAL T GLASS Filed Oct. 11. 1955 Fig. I.

F I l 40 I E I I 35 ii a +1 68 42 i as f 45 l fif J M r Inventors:

John F Donovan, Frank J. Malloy,

Their Attorney.

Patented'June 21, 1938 PATENT orlea 7 2,121,027. Arum-ms ,Foa f same METAL 'ro amiss John F. Donovan, East Cleveland. and Frank J. Malloy, Cleveland Heights, Ohio, assignors to General Electric Company, a corporation of New York Application October 11, rasaseriar No. 44,550

1 Claim.

Our invention relates to apparatus for manufacturing electric lamps and similar articles and more particularly to sealing machines. I

One of the objects of our invention is to provide 5 a machine for effectively and emciently sealing a terminal member, such as a metal disc, directly to an end of a glass bulb.

According to our invention, the machine comprises a turret having thereon a plurality of 1 heads each comprising a support for the metal terminal member, a holder for holding the bulb with its end abutting against the terminal member, and means for pressing the bulb against the said terminal member while a flame is directed 15 against said terminal .member to heat it and to fuse and seal thereto the portion of the bulb in contact therewith. A stop is preferably provided to automatically limit the downward movement of the bulb during the fusion of its end. 20 Further features and advantages of our invention will appear from the following detailed description thereof and from the drawing.

In the drawing Fig. 1 is a side elevation, partially broken away, of a sealing machine com- 25 prising our invention and Fig. 2.is a top view of one-half of said machine, also partially broken away.

The machine comprises in this particular instance six heads ||l which are equally spaced 30 around a turret The heads |0 are preferably loaded and unloaded at one position, the loading consisting in placing the metal disc l2 on a spindle l3 and the tubular bulb l4 in jaws |5--|6. The metal disc I2 is of the type covered in ap- 5 plication Serial No. 3,334, H. D. Blake, filed January 24, 1935; and assigned to the assignee of the present application and has an indented portion l2 which fits snugly over the end of the spindle I3. The disc l2 also has an exhaust tube I1 40 sealed thereto which extends downwardly into the said spindle. The spindle I3 is mounted in a hollow post l3 extending from the turret H in which it is held by a screw Ill. The bulb I4 is engaged by V-notched blocks 20 on the upper 45 and lower portions of each of the jaws l5 and Hi. The said jaws are separated to permit insertion of the bulb therebetween by pressure on lever 2| The jaws |5-|6 are rotatably mounted on pins 22 and 23 respectively in the bracket 24 50 and are prevented from slipping oil the lower ends of said pins by a collar 25 which is clamped to the end of each pin. The lever 2| is operated manually by pressure on pad 26 and turns about pin 21 in the bracket 24, pulling wedge 23 from 55 between the rollers 23-40 on the jaws |I--.|3.

The jaws are then opened by a spring 3| extending between posts in said jaws and a bulb I4 is inserted therebetween with its lower end abutting against the disc l2. The Jaws |5-|6 are then closed by the wedge 23 which is again 5 forced between the rollers 23-30 by a return movement of the lever 2|. The wedge 28 slides in ways in the bracket 24 and is provided with a pin 32 which extends into a hole in one end of lever 2|. The return movement of lever 2| is produced by a spring 33 which extends between posts in bracket 24 and lever 2| respectively and pulls the lever 2| back, thereby moving the wedge 28 into position between the rolls 23 and 30. Bracket 24 is mounted on a pair of rods 34-35 extending upwardly from the bracket 38 which is mounted on the post I8 which is attached to the turret ii and to the lower half 31 of a rotary valve.

After the bulb l4 has been placed in the jaws go l5|6 a weighted tube 33 is swung over and onto the disc 33 on the upper end of said bulb l4 causing saidj bulb l4 to be pressed more firmly against the disc I2. The said tube 33 is mounted in bracket 40 which is slidably mounted on rod 34 so that it may be turned and moved vertically on said rod as required. The tube 33 is pressed down 'by a weight 4| mounted on the upper end thereof and is slotted at 42 to provide clearance for an exhaust tube 43 in some instances extending from disc 33. The turret II is now indexed manually.

In order that the turret may be indexed a catch 44 (Fig. 2) is swung outward away from a pin 45 in the turret by manual rotation of a post 46 on which the catch 44 is mounted and which is preferably rotated by a foot pedal (not shown). The catch 44 is swung back before said head H) is fully indexed and another pin 45 suitably placed in the turret strikes a latch 41 swinging it outward. When the new position of the heads is reached the pin takes the position shown in Fig. 2 and the latch 41 swings in behind the pin, preventing clockwise rotation of the turret.

The said latch 41 is mounted on a screw 48 on 5 the catch 44 and is engaged by one arm of a spring 49 which is mounted on a screw 50 on the catch 44. The other arm of the spring 49 engages a pin 5| on the catch 44.

At the second position of the head IO 9, com- 50 bustible gas mixture is caused to flow through a burner 52 and is ignited by a stationary flame (not shown). The burner 52 comprises a hollow body portion 53 surrounding the upper end of the spindle l3 and a plate 54 which closes off the in-' u terior thereof except for a space directly below the disc l2 wherethe flame is produced. The flame is directed against the disc I! so that only the glass of the bulb it in contact therewith is' the studs 62 press the halves of the valve together. An arcuate passage 85 is provided in the upper valve half 6| to carry the combustible gas mixture from pipe 86 to the passage 55 of the head as it passes through the three positions following the loading position. As the bulb ll passes through these positions it is sealed to the disc I! as shown at the left in Fig. 1 and at the next two positions the heated parts are allowed to cool. The end of the bulb I4 is preferably provided with a flange 61 which is smaller in diameter than the remainder of the bulb as shown at the right in Fig. 1 and which melts down onto the upper sin-face of the disc l2. when the flange 81 is completely meltedthe stop screw 68 in the weighted arm 40 strikes the stationary 30 collar 88 on rod 34, thereby preventing further 9,191,697 a v, s a

vertical movement of the bulb. The upper ends of the rods :4 and a are attached to a plate 1| -for increased rigidity.

What we claim as new and desire to secure by Letters Patent of the United States is:

In a sealing machine, the combination of a turret rotatably mounted on a vertical axis, a plurality of heads mounted on saidturret, each of saidiheads comprising a vertically disposed spindle adapted to hold a metal disc on its upper end and a pair of Jaws disposed above said spindle and adapted to hold a tubular glass bulb in a vertical position with its lower end abutting against the upper surface of said disc, a burner surrounding the upper part of said spindle and having an annular opening therein around the upper end of said spindle for directing a flame at the bottom of the disc on said spindle to heat said disc and cause' the end of the bulb abutting against the disc to be fused and sealed thereto, means for pressing said bulb downwardly as the lower end thereof is fused down, a stop for engaging said means and limiting the downward movement of said bulb and means for causing gas to be supplied to the said burners as the heads carrying them are indexed from a loading position. 7

. JOHN F. DONOVAN. FRANK J. MALIOY. 

